Am I wrong for this?

My boyfriend and I have been together for 6 years. He has twin daughters who are 11. They're great kids and easy to get along with. My boyfriend has full custody of his children so throughout our relationship date nights have been pretty rare. I understood the situation going in to the relationship but now 6 years in, I'm starting to feel some resentment. I know I'm wrong for that. I'm being selfish. But part of me feels really sad I've spent the last few years of my 20s and first few years of my 30s not getting to go out and have date nights and do quality things together just us. We do rarely. But when we do it's the one or two things we always do. It's never anything new or exciting. I wanted so badly to take him on a trip for his upcoming 40th Birthday but he's not willing to find a sitter for more than a night so whatever we do would be super limited. If we even get to go this would be our 2nd "trip" together in 6 years. The last one was nearly 5 years ago when we had 2 nights away. We have taken a couple trips together in that as a family with his kids and those were great trips. But am I wrong for feeling resentful and upset that we aren't getting those date nights and little trips away together. I just hate the idea I'll be nearly 40 before his kids are grown and we can finally start doing those romantic things together I've always wanted.

Am I wrong for this?
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